
Minimum flow
If the pump starts with the valve closed, the energy that
pump delivered to the liquid is transferred in the form
of heat, which may result in rapid temperature increase
of liquid in a short time, cause damage to the parts
and components inside the pump. Therefore, quickly
open the water discharge valve when the pump reaches
operating speed. In case the operating conditions of
pump inevitably reaches zero flow or the hot water is
in circulation, related overflow valve must be provided
or a bypass line should be provided for smaller system.
It is recommended to determine a min. flow or design
an auxiliary line
Zero load protection
In no case the pump is allowed to run with zero load
as such operation will result in extra high pump
temperature and damage the parts and components of
pump (e.g. mechanical seal).
Backflow
When the system runs under pressure in a closed status,
the pressure cannot be reduced via pump, as it may
cause a backflow speed far above the pump speed and
thus damage the system
When using, the user should consider the effect of
various factors on the use, and its maximum suction
height H should be lower than the calculated value
below (negative value should be inverted). Otherwise,
the pump will not work properly.
Pb: local atmospheric pressure unit bar(sea level is
1bar)
NPSHr: water pump must be cavitation margin, unit m
Hf: loss of inlet pipe in m
Hv: liquid saturated vapor pressure unit is m (converted
to water column height)
Hs: safety margin in m (usually 0.5m)
Such as:
Pb=1bar, pump cavitation margin NPSHr=2m,
Pipe loss Hf=2m, safety margin Hs=0.5m
When liquid temperature 40 ℃ saturated vapor
pressure
Hv=Pv/ min, g=0.7m (converted to height of water
column)
H = 1 x 10.2-2-2-0.7-0.5 = 5 m
2 Introduction of pump
2.1 Configuration and application
GLC series pipeline pump is a single stage single
suction vertical centrifugal pump with extended shaft
design and with no bearing body component at the
pump head; the suction and discharge flanges of the
pump are of the same size and the flange centerlines
are at the same axis. The pump rotates clockwise
viewing from the driving end. This pump is suitable
for heating system, air conditioning system, cooling
system, water supply and other industrial systems.
2.2 Type and technical parameters
2.2.1 Vertical single pipette pump
GLC 50 - 160 - 3kW/2
Number of poles of electric motor,
For example, 2-2P
Rated output of electric motor(kw)
For example, 3-3kw
Nominal diameter of
impeller(mm)
For example, 160=160mm
Suction/discharge diameter of
pump (mm)
For example, 50-DN50
Product series--GLC series
product
Technical parameters:
Maximum flow rate: 1900m3/h
Maximum head: 160m
Work pressure: 1.6mpa, 2.5mpa (please check Xylem)
Inhalation pressure: less than 1.0mpa (greater than
1Mpa, please consult Xylem)
Medium temperature: 15 ℃ ~ + 120 ℃
Seal: mechanical seal
Inlet and outlet diameter: DN40 ~ DN350
Inlet and outlet flanges conform to GB/T 17241.6
standard
It can also be produced according to user requirements